Automatic platen printing press



Feb. 4, 1958 BUTTNER Er AL 2,821,917

AUTOMATIC PL'ATEN PRINTING mass Filed Dec. 24, 1954 1 v 4 Sheets-Sheet 1Illlllllllllllm INVENTORS ARTUR BUTTNER HERMANN 'KOCHER A. BUTTNER ETALAU'IIOMATIC PLATEN PRINTING PRESS Q Feb. 4, 1958 4 Sheets-Sheet 2 FiledDec. 24, 1954 INVENTORS ARTUR BUTTNER HERMANN KOCHER V ATTORNEY A.BUTTNER ETAL AUTOMATIC PLATEN PRINTING PRESS 'Feb. .4, 1958 4She'ets-Sheet 3 Filed Dec'. 24, 1954 INVENTORS ARTUR BU TTNER HERMANNKOCHER ATTORNEY Feb. 4, 1958 A. BUTTNER ETAL 2,821,917

AUTOMATIC PLATEN PRINTING PRESS,

Filed Dec. 24. 1954' 4' Sheets-Sheet 4 INVENTORS ARTUR BUTTNER BYHERMANN OCHER ATTO R N EY AUTOMATIC PLATEN PRINTING PRESS Artur Biittnerand Hermann Kocher, Heidelberg, Germany, assignors toSchnellpressenfabrik Aktiengesellschaft Heidelberg, Heidelberg, Germany,a corporation of Germany Application December 24, 1954, Serial No.477,506

Claims priority, application Germany December 30, 1953 1 Claim. (Cl.101-299) The present invention relates to automatic platen printingpresses and particularly to a press of this type provided with means forinterrupting the printing operation.

In a platen printing press, mechanism is provided for moving the platenand type bed toward and away from one another with an oscillating orreciprocating motion. For example, the type bed may be stationary andthe platen reciprocated or oscillated toward and away from the type bed.While the platen is away from the type bed, a previously printed sheetis removed and a fresh sheet to be printed is positioned on the platen.The platen then moves toward the type bed and pressure is appliedbetween the platen and a form mounted on the bed to print the sheetcarried by the platen. The term form is herein used in a generic senseto designate type, plates, mats or other printing media which may bemounted on the type bed in any convenient manner. When faults occur inthe sheet supply during printing, it is necessary quickly to interruptthe operation of the press to prevent the dressing surface on the platenfrom being printed or to prevent the platen from being overloaded. In apower operated press, it is not feasible to stop the press suddenlybecause of the momentum of the power drive. The press is thereforeprovided with a device for varying the stroke of the platen so that,although the press continues to run, the platen is not moved all the waytoward the type bed and no printing pressure is applied. Means isprovided for shifting quickly from an on position in which printingpressure is applied when the platen is moved toward the type bed and anoff position in which movement of the platen toward the type bed iscurtailed so that no printing pressure is applied.

Ink is applied to the form on the type bed each time the platen movesaway from the bed. The inking mechanism may, for example, comprise aninking cylinder and a plurality of rollers for feeding ink to thesurface of the cylinder. If the printing operation is stopped, forexample because of faulty alignment of the sheets to be printed, thepress nevertheless continues to run under no load conditions and theinking mechanism continues to supply ink to the form on the type bed.Because of the continued inking of the form while the press is idling,the first sheets printed when the printing operation is resumed receivetoo much ink and cannot be used. It thus frequently occurs that, becauseof repeated interruption of the printing operation, a considerablenumber of sheets become useless and must be thrown away as waste paper.

It is an object of the present invention to overcome this disadvantageby automatically inteti'liptlng' the feed of ink to the printing formeach time the printing operation is interrupted, even though the presscontinues to idle. Hence, when printing is resumed, the printing form iscorrectly inked and the waste of paper due to overinking is avoided. Inaccordance with the invention,

2,821,917 Patented F ch. 4, 1958 the automatic interruption of the inksupply when the press is idling is accomplished by simple mechanismwhich is virtually infallible in its operation.

In some instances, for example in starting up a press, it is desirableto permit ink to feed to the inking cylinder and the printing form, eventhough the press is idling. In accordance with the invention, means isprovided for blocking out the automatic interruption of the ink supplywhen the press is shifted to idling so that the supply of ink ismaintained. A further feature of the invention is that means forinterrupting the ink supply is operatively connected by a resilientconnection with means for shifting the press so that printing pressureis not applied to the platen. This resilient conection permits the pressto be shifted to idling at any phase in its operation without damage andalso permits the inking to be continued even when the press is idling,if desired. When the printing operation is resumed, the means forinterrupting the ink supply is deactivated in a positive manner so as toavoid any failure in the supply of ink to the printing form.

The objects and advantages of the invention will be more fullyunderstood from the following description and claims in conjunction withthe accompanying drawings which show preferred embodiments of theinvention and in which:

Fig. 1 is a diagrammatic vertical section through a platen printingpress embodying the invention;

Fig. 2 is an enlargement of a portion of Fig. 1 showing additionalmechanism which, because of the small scale, is omitted from Fig. l forthe sake of clarity;

Figs. 3 and 4 are diagrammatic sections similar to Fig. 1 but withcertain parts omitted and showing another embodiment of the invention intwo operational positions; and

Figs. 5, 6 and 7 are views similar to Fig. 2 but show a furtherembodiment of the invention in three operational positions.

In Figs. 1 and 2, there is shown a printing press having a frame 1 and aplaten 2 which is pivotally mounted in the frame to swing about an axis2a so as to move toward and away from a type bed 3 on which there ismounted a printing form 3a. The platen 2 is swung about its pivot 2awith an oscillatory motion by means of a pair of toggle levers 4, eachcomprising a link 4a pivotally connected to the platen at 4c and a link41) pivotally supported by a shaft 6. At their contiguous ends 4d, thelinks 4a and 4b are pivotally connected to each other and to aconnecting rod 5 operated by a crank shaft 5a. The shaft 6 of the bellcrank lever 4 is supported by an eccentric bushing 7 which in turn isrotatably mounted in the machine frame and may be swung by means of anarm 8 fixed to the bushing and a shift rod 9 which is pivotallyconnected to the arm 8 and extends out through an opening 9a in theframe of the machine. The rod 9 is movable in a lengthwise direction soas to swing the eccentric bushing between two positions. In one of thesepositions, the platen 2. is pressed against the printing form with thehighest possible pressure while, in the other position, the shaft 6 ismoved in a direction away from the platen so that no pressure is exertedby the platen on the printing form and preferably the platen surfacedoes not come into contact with the form. Fig. 1 shows the shift rod 9,and consequently the eccentric bushing 7 and shaft 6, in thepressure-applying position. The shift rod '9 is releasably held in theposition shown by means of .a catch 9b which is released by lifting theouter end of the rod. When it is desired for the press to idle so thatno printing pressure is applied between the platen and the printingform, the

rod 9 is lifted to release it and shifted toward the right, as

viewed in Fig. 1, thereby rotating the eccentric bushing 7 in acounterclockwise direction and moving the shaft 6 toward the right.

The operation of the inking mechanism is also controlled by movement ofthe rod 9. On one end of the eccentric bushing 7 or on a collar fixedthereto, there is provided a fixed pin 10 to which there is linked a rod11 which extends up through the machine frame to a position below theinking mechanism. A bell crank 12, pivotally mounted at 13 on themachine frame, has a forked end 12a which straddles an upper end portionof the rod 11 and is engaged by a compression spring 14 which surroundsthe rod 11 and is confined by a collar 14a fixed on the rod. The spring14 normally urges the forked arm 12a of the bell crank up against anenlarged head 27 on the upper end of the rod 11. The inking mechanismcomprises an inking cylinder 13 from which ink is carried to the form inusual manner by other rollers not shown in the drawing. Ink is suppliedto the inking cylinder 18 by means of a fountain cylinder 20 whichreceives ink from a duct 20a, a ductor 16 and transfer rollers 21 and21a. The ductor 16 is carried by arms 16a fixed to a shaft 15 which isrotatably supported by the frame to permit the roller 16 to swing fromthe solid line position shown in Fig. 1 in which it picks up ink fromthe fountain cylinder 24 to a position to the left in which it transfersink to the roller 21. The bell crank lever 12 has a second arm 12bwhich, by angular movement of the bell crank about its pivot 13, isswingable from the position shown in solid lines (Fig. 1) to a positionto the left in which it lies in the path of an arm 17 fixed to the shaft15 of the arms 16a carrying the ductor 16.

When printing is commenced, the rod 9, eccentric bushing 7, connectingrod 11 and bell crank lever 12 are all in the positions shown in solidlines in Fig. 1. The arm 12b of the bell crank 12 is out of the path ofmovement of the arm 17 fixed on the shaft 15 of the ductor andconsequently does not interfere with the oscillation of this ductor. Theductor hence may without hindrance carry out its usual reciprocatingmovement between the fountain cylinder 20 and the ink-transmittingroller 21 so as to transmit the ink received from the ductor cylinder tothe transfer rollers and hence to the inking cylinder 18. Oscillation ofthe ductor is effected in usual manner by suitable mechanism (notshown).

Fig. 1 shows the parts in position for printing. When it is desired tointerrupt the printing operation, for example because of faultyalignment of the sheets to be r printed, the rod 9 is lifted so as torelease the catch 9b and is shifted longitudinally in the direction ofthe arrow 22, thereby rotating the eccentric bushing 7 in acounterclockwise direction and moving the shaft 6 toward the right(Fig. 1) so as to release pressure from the platen. Rotation of thebushing 7 moves the connecting rod 11 upwardly and, through theresilient connection provided by the spring 14, causes the bell crank 12to turn in a counterclockwise direction so that the arm 12b comes intothe path of movement of the arm 17, as indicated by the curved arrow 19.With the bell crank in this position, the arm 17 on the shaft 15, duringits downward movement, strikes the end of the arm 12b of the bell crank12, thereby locking the movement of the ductor 16 in the directiontoward the fountain cylinder 29, thereby preventing the ductor fromcoming into contact with the cylinder. In this manner the transfer ofink from the fountain cylinder 21 to the inking cylinder 18 isinterrupted. It will be understood that the ductor oscillating linkage,of which arm 17 is a part, is provided, in known manner, with aresilient connection (not shown) in Order that arm 12 may preventoscillation thereof without breaking said linkage. As the movement ofthe ductor 16 in a direction toward the fountain cylinder 21) is, inknown manner, effected by means of a spring, the blocking of this ductorin the manner described is readily effected.

If it is desired to allow the ink to be fed during a period when thepress is idling, it is necessary to cancel out the blocking of theductor movement. For this purpose, there is arranged on the supportingpin 23 (Fig. 2) of the arm 12a of the bell crank a further bell cranklever 24, which is swingable within predetermined limits and normallyassumes the position indicated by broken lines 24, 25'. The arm 25 islonger and heavier than the arm 24 so that the bell crank 24, 25 isbiased by gravity toward the position shown in broken lines. When thearm 25 is swung upwardly to the position shown in solid lines (Fig. 2),it is adapted to engage a fixed abutment 26 on the machine frame,thereby locking the bell crank 12 in the position shown in solid linesso that it is out of the path of movement of the arm 17 and hence doesnot interfere with the normal oscillation of the ductor 16. This lockingof the bell crank lever 12 in its released position is effected byswinging the arm 25 to its upper limit while simultaneously turning thebell crank lever 12 against the action of the spring 14 when the rod 9is in idling position. The pressure of the spring 14 tends to swing thebell crank 12 in a counterclockwise direction and thereby presses thelocking arm 25 against the fixed abutment 26 so as to retain it inlocking position. The feeding of ink to the inking cylinder 18 is thuspermitted, even when the printing operation is stopped and the press isidling.

On resuming the printing operation by pulling out the rod 9 in adirection opposite to the arrow 22, the connecting rod 11 is pulleddownwardly so that the head 27 on the end of the rod strikes the arm 12aof the bell crank 12 and swings the bell crank in a clockwise direction.If the locking arm 25 has been set in locking position, as describedabove, the downward movement of the connecting rod 11 relieves thepressure by which the locking arm 25 was frictionally held against thestop 26 and the arm 25 thereupon swings by gravity to the positionindicated by broken lines at 25. Thus, the initial state isautomatically restored so that the bell crank lever 12 is no longerhindered in its function and, when it becomes necessary to stopprinting, the inking mechanism or the ink transfer is automaticallyblocked out of operation as before.

Figs. 3 and 4 show a modified embodiment of the operative connectionsbetween the printing starting and stopping device and the inkingmechanism. A lever 32 is fixedly mounted on a shaft 31 rotatablysupported by the side wall of the machine frame and, at its end, carriesa roller 33 which rests on a rod 34 for starting and stopping theprinting operation. The lever 32 is located inside the machine frame. Onthe outside of the wall 30, the shaft 31 carries an arm 35 to the outerend of which is connected the lower end of a rod 36. On the upper end ofthe connecting rod 36, there are provided fixed collars 37 and 38 with aspring 39 between them. An arm 40 of a two-armed lever 40, 42, pivotallysupported on a fixed shaft 41, is pivotally connected to a sleeve 40awhich is slidable on the rod 36 and is confined between the upper collar38 and the upper end of the spring 39. This provides a resilientconnection between the arm 40 and the rod 36 when the rod is moved in anupward direction and a positive connection when the arm is moved in adownward direction. The second arm 42 of the lever carries a hook-likeprojection 43 adapted to cooperate with a projection 44 on a lever 47which is rigidly mounted on the pivotal axis 45 of the ductor 46 of theink-feeding mechanism which is like that shown in Figs. 1 and 2. Duringnormal printing, all the parts assume the positions illustrated in Fig.3. The projection 43 on the arm 42 is spaced above the projection 44 ofthe arm 47 and hence the movement of the arm 47 and resulting movementof the ductor 46 in normal manner may thus be effected withoutinterference.

In order to stop the printing, the rod 34 is lifted to release it andpushed inwardly in the direction of the arrow 48, whereby printingpressure is released, as described above in connection with Figs. 1 and2. Owing to the arcuate movement of the arm 8 to which the lower end ofthe lever 34 is connected, the portion of the lever engaging the roller33 on the arm 32 is swung upwardly, thereby swinging the arms 32 and 35in a counterclockwise direction and lifting the connecting rod 36.Upward movement of the rod 36 acts through the collar 37, spring 39 andarm 40 to swing the arm 42 downwardly so that the projection 43 on thearm 42 is brought into the path of movement of the projection 44 on theoscillating lever 47. The projection 43 is thus engaged by theprojection 44, thereby preventing the swinging movement of the lever 47and the ductor 46 in the direction toward the fountain cylinder 49.Hence, the inking mechanism receives no further supply of ink from thefountain cylinder.

To permit the actuation of the inking mechanism so as to supply ink evenwhen the printing is stopped, i. c. with the parts in the position shownin Fig. 4, there is provided a catch 50 which is pivotal about a fixedpin 51 on the machine frame and normally hangs by gravity in theposition shown in full lines (Fig. 4). The doublearmed lever 40, 42 isprovided with a projecting surface 52 opposite the catch 50. By downwardpressure on the arm 40 against the action of the spring 39, the lever40, 42 can be swung so that the catch 50 may be brought into a positionwith its end face 53 abutting against the surface 52. The catch 50 isretained in this position by the operational pressure between thesurfaces 52 and 53 produced by the spring 39. The abutment of the catch50 with the surface 52 holds the lever 40, 42 in such position that theprojection 43 lies above the projection 44 and hence does not interferewith the swinging of the arm 47. Thus, the ductor 46 may now freelyoscillate between the fountain cylinder 49 and the first inking roller,even though the printing press is idling and the starting and stoppingrod 34 is in the position shown in Fig. 4 so as to prevent operationalpressure between the platen and the printing form.

When printing is again started, the rod 34 is pulled outwardly in adirection shown by the arrow 48. The connecting rod 36 is thereuponmoved downwardly and the collar 38 engages the arm 40 so as to swing thelever 40, 42 in a clockwise direction and lift the projection 43 out ofthe path of movement of the projection 44 on the oscillating arm 47. Theparts are thus restored to the position shown in Fig. 3. If the catch 50has been engaged, downward movement of the connecting rod 36 relievesthe pressure between the end face 53 of the catch 50 and the surface 52on the lever 40, 42 so that the catch 50 is free to swing by gravity tothe position shown in Fig. 3 and is thereby released. In this manner,the automatically acting connection between the printing startand-stoprod on the one hand and the inking mechanism on the other hand becomesfully effective again so that, with each successive stopping of theprinting, the inking mechanism is automatically put out of operation.

The interruption of the ink supply may, of course, be effected by actingon other parts of the inking mechanism. A further possibility isillustrated diagrammatically in Figs. 5 to 7 according to which the inksupply is interrupted by swinging a friction roller 60 out of its normaloperating position. The friction roller 60 is, for this purpose, carriedby levers 62 which are pivotal about an axis 61. One of the levers 62 isprovided with a second arm 63 which is connected by a link 64 with onearm of a double-armed lever 65 pivotally mounted at 65a on the machineframe. The other end of the lever 65 is resiliently connected in themanner described in connection with the previous embodiments with aconnecting rod 66 which in turn is connected in any desired manner withthe device for starting and stopping the printing operation. Whenprinting has been stopped, the friction roller 60 assumes a position inwhich it is swung out of its normal operating position, as indicated inFig. 5. When printing has been started (Fig. 6), the friction roller 60is swung into operational position in which it engages a second frictionroller 67 and the inking cylinder 68 so as to deliver to the inkingcylinder the ink that has been supplied by the preceding cylinders.Arranged below the lever 65, there is a pivotal catch 69 which normallyhangs downwardly by gravity, as shown in Figs. 5 and 6. With theprinting operation stopped, the lever 65 may be swung against the springpressure of the resilient connection with the rod 66 (in a mannersimilar to that described above and the friction roller may thereby bebrought into operating position. The catch 69 may then be swung upwardsto the position shown in Fig. 7 in which it abuts against a stop surface70 on the lever 65. The catch 69 thereby holds the lever 65 in aposition to permit the feeding of ink to the inking cylinder 68 and thespring pressure exerted by the resilient connection between the lever 65and the rod 66 retains the catch 69 in locking position. When printingis again started, the lever 65 is engaged by the upper collar on the endof the connecting rod 66, thus releasing the pressure between the catch69 and stop surface 70 and permitting the catch to drop automatically toits released position, as shown in Figs. 5 and 6. Hence, the mechanismis in condition automatically to stop the feeding of ink wheneverprinting is stopped and to resume the feeding of ink when printing isagain started.

The embodiments of the invention illustrated in the drawings andparticularly described above are intended to illustrate, rather thanlimit, the invention and it will be appreciated by those in the art thatvarious modifications may be made without departing from the invention.For example, in place of purely mechanical connections between theprinting starting and stopping device and the inking mechanism, it ispossible to employ electrical or electromechanical devices utilizingknown instrumentalities such as positively actuated switches,electromagnets, etc. Moreover, the interruption of the ink supply may beeffected at other points, for example by disengaging the connection ofthe fountain cylinder.

What we claim and desire to secure by Letters Patent is:

In an automatic platen printing press, a type bed adapted to have a formmounted thereon, a platen, a toggle lever system for applying pressurebetween said platen and a form mounted on said bed, shift means forrendering said pressure-applying system ineffective, said shift meansbeing movable between an on position in which said pressure-applyingsystem is eifective and an off position in which said pressure-applyingmeans is ineffective, an inking cylinder for applying ink to a formmounted on said type bed, means for supplying ink to said cylinderincluding a movable inking roll, latch means movable between latchingand released positions for releasably holding said roll in an inactiveposition and thereby interrupting the supply of ink to said cylinder,operative connections between said latch means and said shift meansincluding a resilient connection actuated by said shift means forbiasing said latch means toward latching position when said shift meansis moved to olf position, and means for selectively locking said latchmeans in said released position against force exerted by said resilientconnection when said shift means is moved to off position, said lockingmeans being gravity biased toward a releasing position and retained in alocking position by said resilient connection so that upon moving saidshift means to ofi position said inking roll is automatically held bysaid latch means and rendered inactive.

References Cited in the file of this patent UNITED STATES PATENTS989,334 Casey Apr. 11, 1911 2,018,602 Buttner Oct. 22, 1935 2,591,613Rupp Apr. 1, 1952

